> | Lab 5.2.2: Routed & routing protocols - Overview Estimated time: 30 min. Objectives: Compare the characteristics of routed and routing protocols and cite examples of each Examine a router to determine which routed and routing protocols are active Practice commands to determine which routed and routing protocols are supported (show IP route, show protocols, show running config, router ?) Match terms for routed and routing protocols Diagram the relationship between: routed & routing protocols, dynamic & static protocols, interior vs exterior protocols, distance vector, link state & hybrid routing protocols Background: This lab will reinforce your knowledge and understanding of routed and routing protocols, the primary protocols that enable a router to function. You will review examples of each type of protocol and use various IOS commands at the router to discover which routed and routing protocols are currently running or active on the router. You will also use the help facility to explore what protocols the router could support that may not be currently running. Understanding the distinction between routed and routing protocols is critical to mastering the concepts of internetworking. Routed protocols Protocols are the language or rules of communication between devices on a network. Routed protocols are those protocols that can be routed. Layer 3 (network) addressing information is put in the header of the data packet, which enables the packet to get to it's destination across multiple networks. They are also called routable protocols, meaning they are able to be routed. In order for a protocol to be routable the addressing method must have at least two parts; a network number and a node number. It is the network portion of the address that allows a packet to be routed from one network to another. All devices in a network normally run the same routed protocol, which is like a common language, in order to communicate. Most LAN protocols are routed protocols. The most common routed protocol is the Internet Protocol or IP, which is an international standard. IP is sometimes referred to as TCP/IP, but TCP is actually a transport (Layer 4) protocol and is not involved directly with the routable IP protocol that works at Layer 3. In order for a device (workstation, server, router etc.) to communicate on the Internet, it must be running IP. IP addresses are 32 bits and have a network portion and a node portion that is typically assigned by a network administrator. Other routed LAN protocols are Novell's IPX, AppleTalk and Decnet. Routing protocols Routing protocols are used by routers to communicate between themselves in order to dynamically exchange information about the networks they can reach and the desirability of the routes available. They are typically called dynamic routing protocols and they facilitate the process of routing. They are not needed in a small network if only static routes are used. Routing protocol packets take up bandwidth and operate independently of the routed data packets that pass through the network. There is no information in an IP packet that is related to the routing protocol being used. Routers periodically send information about routes (routing tables) to each other so that when they receive a routed protocol packet (such as IP) they know where to send it. If we think of the routed protocol address like an address on a letter, the routing protocol is like a messenger running between the routers to tell them which routes are open and which ones are the fastest. Routing protocols can be broadly categorized based on whether they are interior or exterior, and subdivided by type: distance vector or link state. Interior Routing Protocols Interior routing protocols are used within a private network. As an example, a company may have a number of LANs in different geographical locations that are connected by routers and dedicated WAN links (such as T1 or Frame relay). If all of these routers are under a common administration or autonomous system (not connected through the Internet), then they would use an interior routing protocol. Interior routing protocols can be subdivided by type: (1) Distance vector, (2) Link State, and (3) Hybrid. The distinction is in the metrics they use to select routes and in how routing table updates are stored and exchanged. Exterior routing protocols Exterior routing protocols are used to communicate between autonomous systems and over the Internet. Examples of exterior protocols include Border Gateway Protocol (BGP) and Exterior Gateway protocol (EGP). BGP is the most common exterior routing protocol and the latest version is BGP4. Tools / Preparation: Prior to starting the lab, the teacher or lab assistant should have the standard router lab with all 5 routers set up and have a routing protocol enabled (RIP or IGRP). Workstations with HyperTerminal should be available to console into the routers. Work individually or in teams. Before beginning this lab you may want to read the Networking Academy Second Year Companion Guide, Chapter 5 – Routing Protocols: IGRP. You should also review Semester 3 On-line Lesson 5. The following is a list of equipment required. Standard Cisco 5-router lab setup with hubs and switches Workstations to connect to the routers Console Cable (roll-over) CAT 5 Ethernet Cable from the workstation to the hub or switch Web Site Resources: Routing basics RIP routing protocol IGRP routing protocol EIGRP routing protocol OSPF routing protocol BGP routing protocol EGP routing protocol Tech tips for IGRP and EIGRP routing protocol Configuring IP routing protocols Basic IP addressing and Troubleshooting guide Notes: Step 1 - Review Interior Gateway routing protocols. The following table lists some of the most common interior routing protocols. Fill in the table with the information requested based on your knowledge. You may look up answers in the text or online or use the web site resources. Interior Gateway Routing Protocols
> Routing Protocol | Protocol Type: (distance vector, link state, hybrid) | Developed by: (Vendor / Standards) | Characteristics/Notes
> RIP (v1 and v2) (Routing information protocol) |  |  |
> IGRP (Interior Gateway Routing Protocol) |  |  |
> OSPF (Open Shortest Path First) |  |  |
> EIGRP (Enhanced Interior Gateway Routing Protocol) |  |  |
Step 2 - Check to see which ROUTING protocols the router can understand. Routing protocols enable the router to learn about other routes. To see the list of IP routing protocols supported and the networks and routes that have been learned, use the show IP route command from user mode. Router> show IP route What are some of the routing protocols supported? You can also see the routing protocols supported in an alphabetical list with definitions. Enter privileged mode, then config mode and then use the help by typing router ?. Router(config)# router ? Are the routing protocols listed the same? Step 3 - Determine which ROUTING protocols are in use. You can see which interfaces and networks are defined for the routing protocols in use. This means they will advertise and received routing updates on those interfaces. Use the show run command to see which protocol is active and on which interfaces. Router# show run What routing protocol is being used and which networks will be advertised? Step 4 - Check to see which ROUTED protocols the router can understand. Routed (or routable) protocols enable packets to move from one network to another. To see the list of routed protocols supported, enter privileged mode, then config mode and use the help by typing ?. You will see many commands but you should be able to pick out the routed protocols. Router(config)# ? Which routed protocols can you see in the list? Step 5 - Determine which ROUTED protocols are in use. Each router in our lab is directly connected to at least one network, and most routers are connected to 2 or more networks. To view which routed protocols are in use on your router enter the show protocols command at the user mode. router> show protocols Which routed protocols are in use? On which interface(s)? Step 6 – Fill in the tree diagram of routed and routing protocols. Fill in the boxes on the tree diagram showing the relationship and protocol names for the more common routed and routing protocols. This will help you visualize the tree when working with these protocols. Start at the top with routed and routing then branch off into interior, exterior, distance vector, link state, etc. Use the abbreviations and acronyms in the legend at the bottom to fill in the boxes. You must use them all. Legend: IP = Internet Protocol, IPX = Internetwork Packet Exchange, A/T = AppleTalk, D.V. = Distance Vector, L.S. = Link State, HYB = Hybrid, BGP = Border Gateway Protocol, EGP = Exterior Gateway Protocol, RIP = Routing Information Protocol, IGRP = Interior Gateway Routing Protocol, OSPF = Open Shortest Path First, EIGRP = Enhanced Interior Gateway Routing Protocol, INTERIOR, EXTERIOR